Unanswered Questions

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I have 2nd order nonlinear ode I try to solve with Runge Kutta 4th order method in maple but all I get from the out is 1 and 0.This is the equation: theta_ode.mw . How do I do it Or how do I write the code to solve it with maple using  Runge Kutta 4th order method?

Hello

 

I am not that good at english, but i will try to tell you what my problem is. 

 

I have a worksheet in maple where i can't find out to make the results appear. 

 

Maybe it is easiere for you guys to help me if i can send you the document. 

 

Looking forward to hear form you


Regards

Niclas 

Hi,

I have a Matrix whose entries are polynomials in several formal parameters (the matrix is sparse and the polynomials are rather simple, though inverses of the parameters may also arise).
Then, when I compute the kernel with LinearAlgebra-NullSpace, maple naturally gives a basis of solutions over the same ring of polynomials.

Now for some reason there are some parameters that I don't want to see in the solutions (all but two of them, actually).

How can I compute the part of the kernel that lives in $\mathbb{Z}[a,a^{-1}, b,b^{-1}]$, i.e. that involves only the first two parameters?

Thank you,

NoThik

Edit : the coefficients of the polynomials are integers, and I expect the kernel elements to have integer coefficients as well.

Dear All,

please help me with my problem. i have quite a big program all parts of which are distributed in the several code edit regions and in the main text. i'd like to find all occurenses of gven text in all open documents including code edit regions. i know how to do it manually by openening each code edit regiong and pressing Ctrl-F. however it is very time consuming and defocuses me apart from my main tasks. i'd prefer to use some combinations of 'hot keys' on the keybord or one or two mouse clicks as for example in MS Visual Studio.  

4(x-7) =6

 

(2x+3)(2x2-5x-3)=0

I am creating a plot in Maple17 which will include many line segments and polygons.  I want the axes to be equally scaled, so that line segments that are perpendicular actually look perpendicular.  When I view what I have created so far, line segments that are perpendicular do not appear to be so in a plot, even though I used the "scaling=constrained" option several times.  I created a stripped-down file that isolates the problem.  Here it is:

restart:

with(plots):

segp := proc(pt1, pt2)
  description "plot of line segment between two points";
  local m;
 m:=Matrix([pt1,pt2]):
  polygonplot(m,thickness=1,scaling=constrained);
end proc:

slope := proc(pt1, pt2)
  description "slope of line segment btwn two different points";
  (pt2[2]-pt1[2])/(pt2[1]-pt1[1])
end proc:

 

 

pa9:=[0.1864032968, 0.9824733131];

[.1864032968, .9824733131]

(1)

pa16:=[0.6816387600, 0.7316888689];

[.6816387600, .7316888689]

(2)

pd9:=[0.05940746930, 0.7316888689];

[0.5940746930e-1, .7316888689]

(3)

slope(pa9,pa16)*slope(pa9,pd9);

-1.000000000

(4)

display({segp(pa9,pa16),segp(pa9,pd9)},scaling=constrained);

 

 

 

 


Download perp.mw

 



An angle that should be a right angle looks obtuse in the plot.  I used "scaling=constrained" in both the "display" command and the "segp" procedure.  I am using "polygonplot" to plot line segments (degenerate polygons) because the final plot will contain genuine polygons and this seemed like the easiest way to do it.  If this is a bad idea for some reason I can change it.

 

GS

according to this page  http://www.maplesoft.com/products/maple/new_features/codeeditor.aspx

it says "Maple 17 features a completely new editor for writing Maple code."  but for the last 15 minutes I've been looking in my Maple 17.02 for windows and not able to figure where this editor is or how to start it.

When I open Maple, I say File->New-> and nothing there for an editor.

I also looked in my Maple installation icons group, there is nothing there.

I also looked here http://www.maplesoft.com/support/help/Maple/view.aspx?path=updates/Maple17/CodeEditor

"Maple 17 features a completely new editor for writing Maple code.   The editor includes many features to make it easier to write, read, and debug Maple code, such as syntax highlighting, bracket matching, command completion, and automatic indenting. The new editor is available for managing startup code, inline code edit regions, and code attached to embedded components."

but again, does not say anything about how to START it ? Or is this editor a separate apps I need to buy?

 

x11 = [0.208408965651696e-3, -0.157194487523421e-2, -0.294739401402979e-2, 0.788206708183853e-2, 0.499394753201753e-2, 0.191468321959759e-3, 0.504980449104750e-2, 0.222150494088535e-2, 0.132091821964287e-2, 0.161118434883258e-2, -0.281236534046873e-2, -0.398055875132037e-2, -0.111753680372819e-1, 0.588868146012489e-2, -0.354191562612469e-2, 0.984082837373291e-3, -0.116041186868374e-1, 0.603027845850267e-3, -0.448778128168742e-2, -0.127561485214862e-1, -0.412027655195339e-2, 0.379387381798949e-2, -0.602550446997765e-2, -0.605986284736216e-2, -0.751396992404410e-2, 0.633613424008655e-2, -0.677581832613623e-2];
y11 = [ -21321.9719565717, 231.709204951251, 1527.92905167191, -32.8508507060675, 54.9408176234139, -99.4222178124229, -675.771433486265, 42.0838668074923, -12559.3183308951, 5.21412214166344*10^5, 1110.50031772203, 3.67149699000155, -108.543878970269, -8.48861069398811, -521.810552387313, 26.4792411876883, -8.32240296737599, -1085.40982521906, -44.1390030597906, -203.891397612798, -56.3746416571417, -218.205643256096, -178.991498697065, -42.2468018350386, .328546922634921, -1883.18308996621, 111.747881085748];
z11 = [ 1549.88755331800, -329.861725802688, 8.54200301129155, -283.381775745327, -54.5469129127573, 1875.94875597129, -16.2230517860850, 6084.82381954832, 1146.15489803104, -456.460512914647, 104.533252701641, 16.3998365630734, 11.5710907832054, -175.370276462696, 33.8045539958636, 2029.50029336951, 1387.92643570857, 9.54717543291120, -1999.09590358328, 29.7628085078953, 2.58210333216737*10^6, 57.7969622731082, -6.42551196941394, -8549.23677077892, -49.0081775323244, -72.5156360537114, 183.539911458475];
filename = 'C:\Users\Hello\Desktop\testnew51.gif';
k = 10;
for n=1:length(x11)
plot3(x11(1:n),y11(1:n), z11(1:n));
%axis equal;
%axis([0,max(x11),0,max(y11)+10]);
xlabel('x (ft)');
ylabel('y11 (ft)');
title('Projectile Trajectory');
M(n)=getframe;
im = frame2im(M(n));
[imind,cm] = rgb2ind(im,256);
if n == 1;
imwrite(imind,cm,filename,'gif', 'Loopcount',inf);
else
imwrite(imind,cm,filename,'gif','WriteMode','append');
end;
end;
numtimes=3;
fps=1;
movie(M,numtimes,fps);

 

when i magnify the diagram in matlab, it is not a triangle, the diagram is changed, 

would like to draw this and animate this in maple to see whether maple has this problem

 

x11 := Vector([0.208408965651696e-3, -0.157194487523421e-2, -0.294739401402979e-2, 0.788206708183853e-2, 0.499394753201753e-2, 0.191468321959759e-3, 0.504980449104750e-2, 0.222150494088535e-2, 0.132091821964287e-2, 0.161118434883258e-2, -0.281236534046873e-2, -0.398055875132037e-2, -0.111753680372819e-1, 0.588868146012489e-2, -0.354191562612469e-2, 0.984082837373291e-3, -0.116041186868374e-1, 0.603027845850267e-3, -0.448778128168742e-2, -0.127561485214862e-1, -0.412027655195339e-2, 0.379387381798949e-2, -0.602550446997765e-2, -0.605986284736216e-2, -0.751396992404410e-2, 0.633613424008655e-2, -0.677581832613623e-2]):
y11 := Vector([ -21321.9719565717, 231.709204951251, 1527.92905167191, -32.8508507060675, 54.9408176234139, -99.4222178124229, -675.771433486265, 42.0838668074923, -12559.3183308951, 5.21412214166344*10^5, 1110.50031772203, 3.67149699000155, -108.543878970269, -8.48861069398811, -521.810552387313, 26.4792411876883, -8.32240296737599, -1085.40982521906, -44.1390030597906, -203.891397612798, -56.3746416571417, -218.205643256096, -178.991498697065, -42.2468018350386, .328546922634921, -1883.18308996621, 111.747881085748]):
z11 := Vector([ 1549.88755331800, -329.861725802688, 8.54200301129155, -283.381775745327, -54.5469129127573, 1875.94875597129, -16.2230517860850, 6084.82381954832, 1146.15489803104, -456.460512914647, 104.533252701641, 16.3998365630734, 11.5710907832054, -175.370276462696, 33.8045539958636, 2029.50029336951, 1387.92643570857, 9.54717543291120, -1999.09590358328, 29.7628085078953, 2.58210333216737*10^6, 57.7969622731082, -6.42551196941394, -8549.23677077892, -49.0081775323244, -72.5156360537114, 183.539911458475]):

 

 

a1 := Diff(x1(t),t) = k1*x1(t)+ k2*y1(t)+ k3*z1(t) + k4*u(t);

b1 := Diff(y1(t),t) = k5*x1(t)+ k6*y1(t)+ k7*z1(t) + k8*u(t);

c1 := Diff(z1(t),t) = k9*x1(t)+ k10*y1(t)+ k11*z1(t) + k12*u(t);
d1 := Diff(u(t), t) = 0;
ICS:=x1(0)=x11[1],y1(0)=y11[1],z1(0)=z11[1];
sol:=dsolve({a1,b1,c1,d1,ICS}, numeric, method=rkf45, parameters=[k1,k2,k3,k4,k5,k6,k7,k8,k9,k10,k11,k12]);
ans:=proc(p1,p2,p3) sol(parameters=[a1=p1,b1=p2,c1=p3]); end proc:
FitParams:=Statistics:-NonlinearFit(ans, x11, y11, z11, x1, y1, z1, initialvalues=<150e-9>, output=parametervalues);

Error, (in Statistics:-NonlinearFit) initial values Vector has incorrect dimension

a1 := Diff(x1(t),t) = k1*x1(t)+ k2*y1(t)+ k3*z1(t) + k4*u(t);
b1 := Diff(y1(t),t) = k5*x1(t)+ k6*y1(t)+ k7*z1(t) + k8*u(t);
c1 := Diff(z1(t),t) = k9*x1(t)+ k10*y1(t)+ k11*z1(t) + k12*u(t);
ICS:=x1(0)=x11[1],y1(0)=y11[1],z1(0)=z11[1];
sol:=dsolve({a1,b1,c1,ICS}, numeric, method=rkf45, parameters=[k1,k2,k3,k4,k5,k6,k7,k8,k9,k10,k11,k12]);

Error, (in DEtools/convertsys) the ODE system does not contain derivatives of the unknown function u

ans:=proc(p1,p2,p3) sol(parameters=[a1=p1,b1=p2,c1=p3]); end proc:
FitParams:=Statistics:-NonlinearFit(ans, x11, y11, z11, x1, y1, z1, initialvalues=<150e-9>, output=parametervalues);

restart;
with(plots):
with(Optimization):
with(LinearAlgebra):
with(Statistics):
with(DEtools):
x11 := <0.208408965651696e-3, -0.157194487523421e-2, -0.294739401402979e-2, 0.788206708183853e-2, 0.499394753201753e-2, 0.191468321959759e-3, 0.504980449104750e-2, 0.222150494088535e-2, 0.132091821964287e-2, 0.161118434883258e-2, -0.281236534046873e-2, -0.398055875132037e-2, -0.111753680372819e-1, 0.588868146012489e-2, -0.354191562612469e-2, 0.984082837373291e-3, -0.116041186868374e-1, 0.603027845850267e-3, -0.448778128168742e-2, -0.127561485214862e-1, -0.412027655195339e-2, 0.379387381798949e-2, -0.602550446997765e-2, -0.605986284736216e-2, -0.751396992404410e-2, 0.633613424008655e-2, -0.677581832613623e-2>;
y11 := <-21321.9719565717, 231.709204951251, 1527.92905167191, -32.8508507060675, 54.9408176234139, -99.4222178124229, -675.771433486265, 42.0838668074923, -12559.3183308951, 5.21412214166344*10^5, 1110.50031772203, 3.67149699000155, -108.543878970269, -8.48861069398811, -521.810552387313, 26.4792411876883, -8.32240296737599, -1085.40982521906, -44.1390030597906, -203.891397612798, -56.3746416571417, -218.205643256096, -178.991498697065, -42.2468018350386, .328546922634921, -1883.18308996621, 111.747881085748>;
z11 := <1549.88755331800, -329.861725802688, 8.54200301129155, -283.381775745327, -54.5469129127573, 1875.94875597129, -16.2230517860850, 6084.82381954832, 1146.15489803104, -456.460512914647, 104.533252701641, 16.3998365630734, 11.5710907832054, -175.370276462696, 33.8045539958636, 2029.50029336951, 1387.92643570857, 9.54717543291120, -1999.09590358328, 29.7628085078953, 2.58210333216737*10^6, 57.7969622731082, -6.42551196941394, -8549.23677077892, -49.0081775323244, -72.5156360537114, 183.539911458475>;
ICS:=[x1(0)=x11[1],y1(0)=y11[1],z1(0)=z11[1]];
N := Dimension(x11)-1:
sys1 := [Diff(x1(t),t) = k1*x1(t)+ k2*y1(t)+ k3*z1(t), Diff(y1(t),t) = k5*x1(t)+ k6*y1(t)+ k7*z1(t), Diff(z1(t),t) = k9*x1(t)+ k10*y1(t)+ k11*z1(t)];
SS := proc(k1,k2,k3,k5,k6,k7,k9,k10,k11)
local F, V;
if not type([k1,k2,k3,k5,k6,k7,k9,k10,k11],[numeric,numeric,numeric,numeric,numeric,numeric,numeric,numeric,numeric]) then return 'SS'(k1,k2,k3,k5,k6,k7,k9,k10,k11);
elif k1<0 or k2<0 or k3<0 or k5<0 or k6<0 or k7<0 or k9<0 or k10<0 or k11<0 then return 1e100;
end if;
F := dsolve(eval({Diff(x1(t),t) = k1*x1(t)+ k2*y1(t)+ k3*z1(t), Diff(y1(t),t) = k5*x1(t)+ k6*y1(t)+ k7*z1(t), Diff(z1(t),t) = k9*x1(t)+ k10*y1(t)+ k11*z1(t),x1(0)=x11[1],y1(0)=y11[1],z1(0)=z11[1]},{:-k1=k1,:-k2=k2,:-k3=k3,:-k5=k5,:-k6=k6,:-k7=k7,:-k9=k9,:-k10=k10,:-k11=k11}), [x1(t),y1(t),z1(t)], numeric, output=Array([seq(k,k=0..N)]));
V := convert(Column(F[2,1],2),Vector);
Norm(V-x11,2);
Norm(V-y11,2);
Norm(V-z11,2);
end proc:
params := NLPSolve(SS(k1,k2,k3,k5,k6,k7,k9,k10,k11), method=nonlinearsimplex, initialpoint=[k1=.1, k2=.1, k3=.1, k5=.1, k6=.1, k7=.1, k9=.1, k10=.1, k11=.1],evaluationlimit=200):

Warning, limiting number of function evaluations reached

reference from 

http://www.maplesoft.com/applications/view.aspx?SID=1667

when debug

k1=.1; k2=.1; k3=.1; k5=.1; k6=.1; k7=.1; k9=.1; k10=.1; k11=.1;
F := dsolve({Diff(x1(t),t) = k1*x1(t)+ k2*y1(t)+ k3*z1(t), Diff(y1(t),t) = k5*x1(t)+ k6*y1(t)+ k7*z1(t), Diff(z1(t),t) = k9*x1(t)+ k10*y1(t)+ k11*z1(t),x1(0)=x11[1],y1(0)=y11[1],z1(0)=z11[1]}, [x1(t),y1(t),z1(t)], numeric, output=Array([seq(k,k=0..N)]));

 

Warning, The use of global variables in numerical ODE problems is deprecated, and will be removed in a future release. Use the 'parameters' argument instead (see ?dsolve,numeric,parameters)
Error, (in dsolve/numeric) Array/array solutions cannot be obtained for ODE containing unassigned global variables {k1, k10, k11, k2, k3, k5, k6, k7, k9}

x11 := Vector([0.208408965651696e-3, -0.157194487523421e-2, -0.294739401402979e-2, 0.788206708183853e-2, 0.499394753201753e-2, 0.191468321959759e-3, 0.504980449104750e-2, 0.222150494088535e-2, 0.132091821964287e-2, 0.161118434883258e-2, -0.281236534046873e-2, -0.398055875132037e-2, -0.111753680372819e-1, 0.588868146012489e-2, -0.354191562612469e-2, 0.984082837373291e-3, -0.116041186868374e-1, 0.603027845850267e-3, -0.448778128168742e-2, -0.127561485214862e-1, -0.412027655195339e-2, 0.379387381798949e-2, -0.602550446997765e-2, -0.605986284736216e-2, -0.751396992404410e-2, 0.633613424008655e-2, -0.677581832613623e-2]):
y11 := Vector([ -21321.9719565717, 231.709204951251, 1527.92905167191, -32.8508507060675, 54.9408176234139, -99.4222178124229, -675.771433486265, 42.0838668074923, -12559.3183308951, 5.21412214166344*10^5, 1110.50031772203, 3.67149699000155, -108.543878970269, -8.48861069398811, -521.810552387313, 26.4792411876883, -8.32240296737599, -1085.40982521906, -44.1390030597906, -203.891397612798, -56.3746416571417, -218.205643256096, -178.991498697065, -42.2468018350386, .328546922634921, -1883.18308996621, 111.747881085748]):
z11 := Vector([ 1549.88755331800, -329.861725802688, 8.54200301129155, -283.381775745327, -54.5469129127573, 1875.94875597129, -16.2230517860850, 6084.82381954832, 1146.15489803104, -456.460512914647, 104.533252701641, 16.3998365630734, 11.5710907832054, -175.370276462696, 33.8045539958636, 2029.50029336951, 1387.92643570857, 9.54717543291120, -1999.09590358328, 29.7628085078953, 2.58210333216737*10^6, 57.7969622731082, -6.42551196941394, -8549.23677077892, -49.0081775323244, -72.5156360537114, 183.539911458475]):

 

a1 := Diff(x1(t),t) = k1*x1(t)+ k2*y1(t)+ k3*z1(t) + k4*u(t);
b1 := Diff(y1(t),t) = k5*x1(t)+ k6*y1(t)+ k7*z1(t) + k8*u(t);
c1 := Diff(z1(t),t) = k9*x1(t)+ k10*y1(t)+ k11*z1(t) + k12*u(t);
d1 := Diff(u(t), t) = 0;
ICS:=x1(0)=x11[1],y1(0)=y11[1],z1(0)=z11[1];
solL:=dsolve({a1,b1,c1,d1,ICS}, numeric, method=rkf45, parameters=[k1,k2,k3,k4,k5,k6,k7,k8,k9,k10,k11,k12]);
ans:=proc(p1,p2,p3) solL(parameters=[a1=p1,b1=p2,c1=p3]); end proc:
FitParams:=Statistics:-NonlinearFit(ans, x11, y11, z11, x1, y1, z1);

 

Error, (in Statistics:-NonlinearFit) unexpected parameters: Vector(27, {(1) = 1549.88755331800, (2) = -329.861725802688, (3) = 8.54200301129155, (4) = -283.381775745327, (5) = -54.5469129127573, (6) = 1875.94875597129, (7) = -16.2230517860850, (8) = 6084.82381954832, (9) = 1146.15489803104, (10) = -456.460512914647, (11) = 104.533252701641, (12) = 16.3998365630734, (13) = 11.5710907832054, (14) = -175.370276462696, (15) = 33.8045539958636, (16) = 2029.50029336951, (17) = 1387.92643570857, (18) = 9.54717543291120, (19) = -1999.09590358328, (20) = 29.7628085078953, (21) = 2582103.332, (22) = 57.7969622731082, (23) = -6.42551196941394, (24) = -...

So I am working on doing some trajectory simulations in Maple using standard Newton's Laws, some force expressions, and initial conditions.

Anyway, the numerical solution works fine if I let the initial conditions I specified (for z=-1) be actually for z=-0.9. To illustrate, when I give an initial condition like this:

x(-1) = x_0, D(x)(-1) = xd_0, Vz(-1) = v_0

the results don't make any sense. However, when using the same x_0, xd_0, and v_0 and I give initial conditions like this:

x(-.9) = x_0, D(x)(-.9) = xd_0, Vz(-0.9) = v_0,

the solutions at least make a bit of sense.

What's weird is that, when I let z -> 0.93 or so, the solution changes discontinuously. And this shouldn't happen. The initial conditions were calculated for and should work for z = -1. I don't understand why they aren't.

Here is my Maple document. ics1 are the problem.

dsolve_field_traject.mw

Do you guys have any idea what could be going on?

Hello, everyone!


Last week I’ve encountered problems with integration of Maple 17 in Microsoft Office Excel 2013. The Maplesoft note on the point (http://www.maplesoft.com/support/faqs/detail.aspx?sid=32651) offers some ways of fixing it up, though I’ve run all of them the problem is the same:

While the connection is established, after entering the formula “=Maple(“x+x”)”, the Excel returns “Critical Error in Formula”

Before contacting the Maplesoft Technical Support, I want to ask here whether someone had the same case and managed to solve it.

Many thanks in advance.

the question is as follow:

1)receive two integers p and q

2)declare two local p1 and q1 and give them intial values and q

3)check if p o q are equal or less to zero print works only with positive integers

4)while p1 not equal to q1 then p1-a1 otherwise q1-p1

5)whenever p1=q1 we have the GCD

note:must use procedure and call it for different values of p and q after the procedure is written

-by following the instruction above this is what i got

GCD:=proc(p,q)

local p1,q1;

p1:=p;

q1:=q;

if p<=0 OR Q<=0 then 'works only with positive integers'
else while p1<>q1 do if q1<p1 then p1-q1 else q1-p1

end if;

end do;

end if;

end proc;

but when I call two integers eg:p=2, q=6 -> GCD(2,6) maple just freeze...evaluating....forever. is it because i got the procedure wrong etc? it would be helpful if anyone can help me with this. thanks

 

 

A square has 36 sub-squares in it. How to Number each sub squares from 1 to 36, to make the sum of vertical, the sum of horizontal, and the sum of cross line are the same .Describe in general if possible.

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